LCM & HCF YouTube Lecture Handouts
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HCF and LCM - 3 Speed Tricks & 10 Typical Word Problems
LCM & HCF Story with Tree & Circles
Mayank explains the following two key concepts to quickly and easily identify and solve all HCF and LCM problems - 1. Quickly find HCF and LCM using 3 simple tricks in this video. 2. To detect HCF and LCM word problems, use the following keywords: LCM 1. Minimum number of days, rounds etc. 2. Least amount of time, things etc. 3. Smallest number, length, amount of time etc. HCF 1. Maximum (possible) number of days, things etc. 2. Longest (possible) size, length, amount of time etc.
Our Journey
- Factors
- Prime Factors
- Multiples
- Factors and Multiples
- Highest Common Factor
- Common Factors
- Least Common Multiple
- Common Multiples
Understanding Factors
Prime Factors
- Factors which are prime (numbers) are called prime factors
Understanding Multiples
Factors and Multiples
- Factors can (completely) divide the number
< Number
- Multiples are (completely) divisible by the number.
> Number
Factorization Using Tree of Factors
Tree of Factors- 24
Common Factors of 32 and 24
Finding Common Factors (HCF) Using Grouping
Common Multiples of 32 and 24
32 - 32, 64, 96, 128, 160,192, 224, …
24 - 24, 48, 72, 96, 120, 144,168, 192, …
Least Common Multiple - LCM
Lowest common Factor – LCM
Highest Common Multiple - HCH
HCF and LCM Combining the Two Steps
Other Names of HCF
- Greatest Common Factor - GCF
- Greatest Common Divisor - GCD
Why Prime Factors?
✍ Mayank